I upgrade from 11.10 to 12.04LTS. I choose Ubuntu to have a secure system for 5 years. Unfortunately I don't wrote down all packages which get no longer updates from canonical like defoma. So I wonder how I could detect all such packages and remove them? Coming from Debian a command-line solution is preferred, but a GUI solution is acceptable.
Every package that is in
There are some aptitude query examples available; for a ppa-less install this should yield the currently supported list:
However the easiest is to use synaptic, select installed and click on the column with the ubuntu icon. All the installed packages that no longer have this icon are not supported. You can also add a custom filter to synaptic that will achieve your goal.